Regular Expression String Break

Question

I am fairly new to regex. I have been trying to break string to get the initial part of the string to create folders.

Here are few examples of the variables that I need to break.

test1-792X612.jpg

test-with-multiple-hyphens-612X792.jpg

Is there a way using regular expression that I can get test1 and test-with-multiple-hyphens ?

Answer 1

You can use a regex like this:

(.*?)-\d+x\d+

Working demo

The idea is that the pattern will match the string with the -NumXNum but capture the previous content. Note the case insensitive flag.

MATCH 1
1.  [0-5]   `test1`
MATCH 2
1.  [18-44] `test-with-multiple-hyphens`

If you don't want to use the insensitive flag, you could change the regex to:

(.*?)-\d+[Xx]\d+

Answer 2

If you're certain that all filenames end with 000X000 (where the 0's are any number), this should work:

/^(.*)-[0-9]{3}X[0-9]{3}\.jpg$/

The value from (.*) will contain the part that you're looking for.

In case there could be more or fewer numbers, but at least one:

/^(.*)-[0-9]+X[0-9]+$\.jpg/

Answer 3

You can use this simple regex:

(.+)(?=-.+$)

Explanations :

(.+) : Capture desired part

(?=-.+$) : (Positive Lookahead) Which is following a dashed part

Live demo

Answer 4

If I understood your question correctly, you want to break the hyphenated parts of a file into directories. The expression (.*?)-([^-]+\\.jpg)$ will capture everything before and after the last - in a .jpg file. You can then use preg_match() to match/capture these groups and explode() to split the - into different directories.

$files = array(
    'test1-792X612.jpg',
    'test-with-multiple-hyphens-612X792.jpg',
);

foreach($files as $file) {
    if(preg_match('/(.*?)-([^-]+\.jpg)$/', $file, $matches)) {
        $directories = explode('-', $matches[1]);
        $file = $matches[2];
    }
}

// 792X612.jpg
// Array
// (
//     [0] => test1
// )
//
// 612X792.jpg
// Array
// (
//     [0] => test
//     [1] => with
//     [2] => multiple
//     [3] => hyphens
// )